• Sealy Advantage Harper Firm Mattress King Single HAR-FRM-KSG

    $491
    $25 (5%) off RRP of $516
    $25 (5%) off RRP of $516

    Sealy Advantage Harper Firm Mattress King Single HAR-FRM-KSG

    $491
    $25 (5%) off RRP of $516
    $25 (5%) off RRP of $516
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    Mattress Size: King Single
    • Overview
    • Specifications & manuals
    • Reviews
    • Legendary service
    • Delivery, services & returns
    • Questions & answers

    Overview

    Engineered for those who prefer firmer support without sacrificing comfort, the Harper range is a standout solution in sleep technology. This collection combines thoughtful design and durable components to deliver a mattress that holds its shape, supports your posture, and enhances rest for years to come.

    At the core of every Harper mattress is the trusted CoreSupport spring system. This Sealy-exclusive technology features a single-stage, twice-tempered coil system with six active turns, designed to deliver consistent deep-down support while contouring gently to the body's pressure points. It’s a perfect match for sleepers who value firmness, structure, and full-body alignment.

    Harper also includes the innovative EdgeGuard support system, extending the mattress’s usable surface and reinforcing its perimeter. This means a more stable seating edge and confident edge-to-edge sleep support—especially important for those who move around during the night or share their bed.

    HealthShield antimicrobial treatment is integrated into the comfort layers to create a cleaner, healthier sleep environment, while rigorous product testing ensures long-term performance and resilience.

    Perfectly paired with any Sealy base—including standard, adjustable, or storage designs—Harper brings together practicality, hygiene, and superior value. It’s an ideal choice for anyone seeking a firm feel backed by intelligent construction and trusted Australian craftsmanship.
    CoreSupport Spring System

    A resilient, single-stage coil system featuring six active turns for deep-down support and long-term durability, ideal for maintaining posture during sleep.

    EdgeGuard Perimeter Support

    Maximises the sleeping surface with a stabilised edge that offers a consistent feel from centre to edge and superior seated support.

    HealthShield Antimicrobial Layer

    Built-in antimicrobial protection promotes a fresher, more hygienic sleep surface by helping to reduce allergens and odours over time.

    Durable Comfort Architecture

    Premium materials are carefully layered and tested for endurance, ensuring that the firm comfort profile is maintained for years of consistent use.

    Specifications & manuals

    key Specifications
    Brand
    Sealy
    Model Number
    HAR-FRM-KSG
    Height (mm)
    210 mm
    Width (mm)
    1055 mm
    Depth (mm)
    2030 mm
    Weight (kg)
    26 kg
    Bedding Size
    King Single
    Image Disclaimer
    Images used for illustration purposes only. Additional accessories shown are not included.
    Mattress Size
    King Single
    Mattress Feel
    Firm
    warranty
    Manufacturer Warranty
    10 Years
    other Features
    Bedding Type
    Mattress
    Features
    • Firm Comfort Profile: Offers stable, supportive sleep for those who prefer a firmer mattress feel.
    • CoreSupport Coil System: Engineered for long-term support with six-turn coils that contour and reinforce.
    • EdgeGuard Technology: Reinforced perimeter for full-edge support and a maximised sleeping area.
    • HealthShield Treatment: Antimicrobial protection helps create a cleaner, healthier sleep environment.
    • Tested for Endurance: Each component undergoes rigorous testing to ensure long-lasting comfort and performance.
    • Australian Made Quality: Proudly crafted in Australia to meet high manufacturing and sustainability standards.
    • Orthopaedic Design Principles: Supports proper body alignment and helps reduce pressure on key joints.
    • Compatible with Sealy Bases: Designed to pair seamlessly with Sealy's range of standard and adjustable bases.
    • Stable Seating Edge: EdgeGuard ensures dependable support when sitting or lying near the mattress edge.
    assembly
    Assembly Notes
    No Assembly Required
    country of Origin
    Origin
    Australia

    Reviews

    Rating snapshot

    5
    1
    4
    0
    3
    0
    2
    0
    1
    0

    Average customer rating

    Overall
    5.0
    Ease of setup
    5.0
    Build quality
    4.0
    Value of product
    5.0

    Appliances Online's customer reviews are independently managed by Bazaarvoice, ensuring their accuracy and honesty. Vouchers are sometimes offered to verified buyers in exchange for their unbiased review.

    Learn more about Bazaarvoice Authentic Reviews Trust Mark
    1-1 of 1 reviews
    Reggie2025-09-21
    Amazing
    It’s an amazing firm mattress Light enough for elderly people to put fitted sheets in Very satisfied
    Build quality
    4.0
    Ease of use
    5.0
    Value of product
    5.0

    Legendary service

    The Appliances Online Net Promoter Score (NPS) is based on feedback from 89,897 people, collected between August 2024 to August 2025. Learn more about the Net Promoter Score (NPS).
    Excellent !! Very Happy
    Jenny , Sunbury VIC
    My appreciation to management for the professionalism and care
    Geordie,
    I was extremely happy with the product, and particularly the service
    Lisa, Noble Park, Victoria

    Delivery, services & returns

    Appliances Online is all about legendary service. We offer free next business day delivery, free connection, free removal and free recycling, and we even offer Saturday delivery and, in some locations, a Premium Delivery option that allows you to choose your own 2-hour delivery window.

    Questions & answers

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    We're here to help 24/7 - for an immediate answer to your question, chat with one of our Live Chat agents below or call us on 1300 000 500 .

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